package string;

public class StringStringBuilderDemo {
    public static void main(String[] args) {
        StringBuilder s = new StringBuilder("a");
        long start = System.currentTimeMillis();
        for (int i = 0; i < 10000000; i++) {
            s.append(i);
        }
        long end = System.currentTimeMillis();
        System.out.println(end - start);
        System.out.println("执行完毕");
    }
}
